FileCoin本地cid的計算（js版本）

一：前言

由於業務需求，需要本地先計算出filecoin廣播交易成功後的cid，也是踩了好多坑，最終搞定

二：代碼

以下只提供js代碼：

const filecoin_signing = require('@zondax/filecoin-signing-tools')
const cbor = require("ipld-dag-cbor")
const CID = require('cids')
const multihashing = require('multihashing-async')

const privateKey = ''
const message = {
    "to": "f1str7eiaxglndkh5rm7qe4cprlwguwmkoj4xyu5i",
    "from": "f1re27enhjrpp7jnr33iioq6am6w6xodu63aodlha",
    "gasfeecap": "2589446624",
    "gaslimit": 608335,
    "gaspremium": "99562",
    "method": 0,
    "nonce": 52,
    "value": "10000000000000",
    "version": 0,
    "params": ""
}

async function cid() {
    let messageBytes = filecoin_signing.transactionSerializeRaw(message)
    let tranSignBytes = filecoin_signing.transactionSignRaw(message, privateKey)
    let cidBytes = Buffer.concat([
        Buffer.from([130]),
        messageBytes,
        cbor.util.serialize(Buffer.concat([
            //簽名type爲1
            Buffer.from([1]),
            tranSignBytes,
        ])),
    ])
    const hash = await multihashing(cidBytes, 'blake2b-256')
    const cid = new CID(1, 'dag-cbor', hash)
    console.log("cid:" + cid.toString())
}

cid()

三：參考代碼

https://github.com/filecoin-project/lotus/blob/master/chain/types/cbor_gen.go